‘he ship that sank off Antikythera was a freighter (holkas, in ancient Greek) of an estimated capacity of ca. 300 tons. Her physical remains are meager and the wreck, at a depth of some 52m., has not yet been mapped.

Parts of the stern and the prow have not been identified. The ship's hull was built from single planking, in accord with to the 'shell-first' technique, the predominant method of construction in the Mediterranean from the 4th to the 1st centuries BC. In this technique, which is the opposite of the later practice, the structure relies upon a lengthwise constructional layout. In this method, planks are placed parallel to the keel. Frames were inserted in the structure only after the external hull was completed to a certain extent, first the floor timbers followed by the half frames and the futtocks. The size and position of the mortise and tenons (width, length, height, spacing) ensure cohesion and stability. The wooden pegs and tenons used in the Antikythera ship were made of oak (Lat. quercus), whereas the planks were made of elm (Lat. ulmus). The exterior surface of the hull below the waterline was sheathed with thin sheets of lead. Parts of raised lead pipes have been associated with the water drainage pump.

The Corinthian roof tiles (Lat. imbrices and tegulae) suggest the existence of a roofed area on the deck, which very probably served for the preparation of food or/and to protect, by means of the tiles, the retractable wooden doors of the loading hatches.

The ship would have had up to five large anchors. The discovery of two sounding weights for measuring depth and ascertaining the nature of the seabed (anc. Gr. katapeirateriai) gives some indication of the ship's size and the voyages on the high seas that it undertook.

At the period when the wreck occurred, freighters possessed a square sail attached to a central mast and horizontal boom, a triangular sail hoisted at the top of the mast, and an auxiliary side sail.

The ship that sank off Antikythera was probably en route to Italy. It went down off the island's east coast, ravaged by a storm blowing from the east or northeast which implies that the ship was coming from the eastern Aegean.